Servo-motor-controlled unclutching device for internal-combustion engines



P 1929- H. L. MARFAING SERVO MOTOR CONTROLLED UNCLUTCHING DEVICE FORINTERNAL COMBUSTION ENGINES Filed May 1, 1925 2 Sheets-Sheet l 1,729,173Sept. 24, 1929. H. MARFAING SERVO MOTOR CONTROLLED UNCLUTCHING DEVICEFOR INTERNAL COMBUSTION ENGINES Filed May 1, 1925 2 Sheets-Sheet 2- fig.4 L Fig"; 5 fig". 6

4 i r A 1o ferent speeds.

The object of the invention consists n new.

Patented Sept. 24, 1929 I NITED STA TES HENRI anon MARIAING, or 22mmamen, nssrenoa 'ro ooituenm mnemormcmevn, or rams, rnmcnsnavo-moroaconrnomnn uncnu'rcnme DEVICE Ion mramlrmcomnusrron nnemnsApplication filed lay 1,1925, Serial No. 27,885, and in France December81. 1924.

The invention relates to movable or stationary arrangements like thoseof motor vehicles of all kinds, lifting apparatuses and the like whichare provided with a pro- 5 gressive coupling device interposed betweenan internal combustion engine and the mechanism actuated by this engineand partlcularly to those arrangements w 1ch include a system oftransmitting gears providing difmeans constituting a servomotcr withautomatic follow-up device which may be used for unclutching andclutching a progressive coupling device by means of an intermediatedriving element, insignificant value the effort to be made by the driverfor overcoming the effort of the spring which is usually provided forautomatically performing the reclutching.

The invention possesses other advantageous characteristics which will behereinafter described.

Several devices have already been proposed as adapted to suppress inmotor vehicles the fatigue occasioned to the driver by the frequentoperation of the clutching device; in order to overcome the resistanceof the clutching. device, the required efl'ort is produced by devicesutilizing either the electric current or air under pressure suppliedfrom a special compressor, or the mixture of burnt gases compressed bythe engine itself during the exhaust period. These devices involve awaste of power for the engine or a supplementary expense of energy ,theyare moreover expensive and cumbersome, and those which utilize fluidsunderpressure are even, on account of the compressed air or gas tank,dangerous in case the vehicle is damaged. Other devices on the contraryutilize a driving agent which is gratuitiously available upon theengine,

that is to say, the relative vacuum prevailing in the inlet pipe of theengine between the cylinders and the carburetter throttle-valve. Thepresent invention utilizes as driving agent the vacuum so produced inthe inlet conduit of the internal combustion engine; the putting inaction of the said vacuum, and

in viewof reducing to an" the magnitude of its working are suitably regulated b means of a distributing or supply cock which is 'subjected to adouble control, acting firstly under the displacements of a dr verscontrol lever (or pedal) and secondly under the displacements of theunclutching lever, which latter control suppresses the ac- .tion of theformer'as soon as the desired effect of the said source of power uponthe unclutching means has been entirely produced.

In this manner the driver will obtain upon the unclutching lever, therepetition of the movements which he imparts to the control lever orpedal without'bcing obliged to exercise any other efi'ort except what isrequired for operating thesaid supply cock, this efiort being verysmall.

The said arrangement is essentially constituted as follows:

A piston movable in a working or auxiliary cylinder with two closed endsis connected by means of its outwardly extending rod and a flexibleconnecting device with a suitable lever which controls the unclutchingmechanism by the use of elements known per se. By means of theabove-mentioned distributing or supply cook, the two chambers formed inthe cylinder by the said piston may be connected in turn with the vacuumprevailing in the engine inlet or with the atmosphere, or either chambermay be cut off from the same; the

vacuumconnection of one chamber coincides in all cases with theatmospheric connection of the other.

In a similar known device the suction-pipe of thecombustion engine is inunrestrained communication with the atmosphere during nearly all thetime which elapses between the instant of the unclutching and that ofthe consecutive reclutching; thus the engine sucks I a considerablequantity of air which not only reduces the efiicacity of said device,but is prejudicial to the carburetion of the engine and can even causethe same to stop. As it will be seen hereafter, the device according tothe present invention avoids these disadvantages by the fact that thesuction pipe of the engine is in communication with the atmosphere onlyduring the operation of unclutching and that of the consecutivereclutching, whereas said communication is cut ofl during the whole timewhen the clutch remains quite disconnected or quite connected,

so that as often as the device becomes actuated, the engine can onlysuck, in addition to the required air for the carburetion, but theuantity just contained in the auxiliary cylinder on the side at whichthe vacuum 1s to be made.

The said invention will be hereinafter set forth with reference to theappended drawings showing by way of example the appli cation of theinvention to motor vehicles.

Fig. -1 is a diagrammaticview of an embodiment of the invention whereinthe two controls are combined in the distributing cock.

Fig. 2 is a lengthwise section of the said cock, and,

Fig. 3 a cross section on the line 33 of Fi 2.

igs. 4, 5 and 6 are various cross sections of the said cock upon thesame plane, according to the difierent relative positions of the valve.

Fig. 7 shows another embodiment, wherein the two controls are combinedin the device actuating the said cock. For the sake of greaterclearness, the gear casing has been replaced by an open frame.

valve 42 of Fig. 7.

As shown in Fig. 1, the portion 1 of the inlet piping situated betweenthe cylinders 2 and the throttle 3 of the carburettor (not shown) isconnected by the ipe 4 with one of the orifices 27 of the supp y cock 5which also comprises an atmospheric orifice 26 and two lateral orifices24 and 29 which are connected by the respective pipes 7 and 6 with theends of a cylinder 10 co-operating with the fluid tight piston 11.

The rod extending from said piston is connected by a flexible cable 12with a lever 13 which may act, by means of the usual devices, tocompress the spring 14 in order to perform the unclutching; said lever13 has therein the slot 15 in which is slidable an arm) 16 mounted onthe pedal lever 17 which is .controlled by the drivers foot. Therelative motion of the levers 13 and 17 will thus be limited by the slot15. A sprin 18 which abuts against the lever 13 urges t e lever 17towards the drivers foot (position Fig. 1).

Figs. 2 and 3 show the arr'an ement of the said cock; in order tosimplify t e description it will be supposed to be formed withcylindrical elements. The cock body 5 has formed therein the twochambers 25 and 28 communicatin with the respective orifices 24 and 29.he rotary valve 23, or outer valve, has the four rectangular openings35, 36, 37, 38, whereby the openin s 35 and 37 areopposite to oneanother an also 36 and 38 opposite to one another the valve 23 can 65 berotated on its axis by the lever 21 which Fig. 8 is a cross section ofthe simple checkis mounted upon its outwardly extending rod; a secondrotary valve 30, or inner valve, which is coaxial with the said outervalve, comprises four conduits which'are disposed respectively (Fig. 2)in two meridian planes 7 and in two other planes parallel to one anotherand normal to the axis in such a manner, that the two conduits 31, 32,which open into the central conduit 27 form a broken line in the first.transversal plane with the two conduits 33, 34 which open into thecentral conduit 26 form another broken line symmetrical to the firstmentioned one, but in the second transversal plane. The central conduit27 has a vacuum connection (Fig. 1), and the second central conduit 26an atmospheric connection. The outer valve 23 has a definite lap withregard to the inner valve, in such a manner that the conduits 31 and 33cannot be open at the same time neither in the port 38 nor in the port37 and that also the conduits 32 and 34 cannot be at the same time inconnection with one or the other of the symmetrically arranged ports 35and 36 (Figs. 3-6). The inner valve 30 is controlled by the lever 22which is mounted on its outwardly extending rod. The levers 21 and 22are respectively connected with the unclutching lever 13 (Fig. 1) andwith the control pedal 17, by the links 19, 20.

- The operation is as follows:

The parts being so adjusted that when in the inoperative position, i. e.when the device is .not called upon toperform the unclutching, thevalves will have the relative positions shown in Fig. 4, it will benoted that the vacuum in the pipe, 1 (Fig. 1) is propagated by means ofthe pipe 4, the conduit 27 (Fig. 4), the conduit 31 the opening 38, thechamber 28, the orifice 29, the pipe 6, (Fig. 1), to the chamber 8 ofthe cylinder 10; further, the chamber 9 of the cylinder has anatmospheric connection by means of the pipe 7, the orifice 24 of thecock (Fig. 4) the chamber 25, the opening 36, the conduit 34 andthe-con- 110 duit 26 opening into the atmosphere. Due to the differencein the pressure upon its faces, the piston 11 (Fig. 1) will bemaintained in the position indicated, whereby the cable 12 is somewhatslack and has no action upon the unclutching lever 13.

Referring to Figs. 1 and 3, suppose the pedal lever to beprogressivelydisplaced to the right- .(clockwise); then the inner valve 30 which isactuated by the link 20 and the lever 22 will rotate in anti-clockwisedirection and come from the position of rest shown in Fig. 4 into theposition shown in Fig. 5, this latter figure corresponding to theinstant at which the arm 16 of lever 17 reaches the opposite end of theslot 15 in the lever 13. The first part of said displacement correspondsto the lap of the valve, which prevents the central conduits 26 and 27to be brought simultaneously in connection with the same port of theouter valve 23 as above mentioned; during this part of displacement nochange occurs in the above described pipe-connections, but as soon asthe conduits 33 and 32 of the inner valve have reached respectively theedge of the ports 37 and 35 of the outer valve, pressure in the chamber8 of the auxiliary cylinder 10 becomes the same as the atmosphericpressure whilst the o posite chamber 9 has a vacuum connection hence thedifference in pressure on the faces of the piston will now be in thecontrary direction to that previously mentioned and the piston will movein the said cylinder and will draw u on the cable 12 which will be nowstretched, t as actuating the unclutching lever 13.

But the motion of said lever will be imparted through the link 19 andthe lever 21 to the outer valve, and the latter when rotating will tendto close the conduits of the in ner valve which are now operative.

As long as the pedal lever 17 continues to be displaced, the properconduits of the inner valve will coincide with the openings of the outervalve, while remaining in communication with the same chamber of thecylinder 10; so that the said piston will continue to move to the end ofits stroke, or until the openings 37 and 35 are closed by theircoijmilidence with the solid part of the cock But if the said pedallever is stopped and is held in a position such that the inner valve isstopped in the position shown in Fig. 6, the piston 11 and hence theouter valve which is connected therewith b the members 12, 13, 19, 21will move unti the said conduits and ports are out of coincidence, i. e.until the valves come into the relative positions shown in this figure.-Now the arm 16 of the pedal lever 17 will be midway in the slot 15; thevarious parts of the device will remain in this position as long as thepedal lever is held by the driver in the position under consideration.

The action will take place in like manner for the inverse direction;when the driver releases the said pedal lever, it will tend under theaction of the spring 18 to return to the inoperative position, but itsmotion is limited by the arm 16 which makes contact in the slot 15, andsince the allowable displacement corresponds to a rotation of the innervalve such that the vacuum conduit 31 returns into coincidence with theopening 38, and the atmospheric conduit 34 with the opening 36, thepressures on the faces of the piston will thus be reversed, and thelatter as well as the various controlling members will assume theirvarious inoperative positions.

As observed, the controlling lever and the lever compressin the clutch sring are so disposed that the former, a ter moving will enter intoconthrough a given distance,

lever, so thatthe tact-with the unclutching driver may throw off theclutch in the usual manner, for instance in the event of damage to theapparatus.

Fig. 7 shows a modified arrangement according to the invention whereinthe respective action exercised upon the vacuum and the aircommunications by the pedal lever 17 and the unclutching means 13,instead of taking place within the cock itself, which requires the useof two valves, are combined in the controlling device, so that the cocknow comprises only a single check valve.

For this purpose, the levers 13 and 17 are connected by t e respectivelinks 39 and 40 with two crank-levers 41 and 41 (Fig. 17), which arerespectively fastened on the shafts of the two planetary pinions 41 and41 of a differential mechanism 41 (Fig. 7) known per se; said. shaftsbeing journaled in the two hearings on the support 41*. Saidcrank-levers are fastened symmetrically with regard to the plane passingthrough the axis (Ix-02 of rotation of the differential and through thepoints at which the said links 39 and 40 are attached to the levers 13and 17, in such manner that movements of the levers 13 and 17 in thesame direction will cause said planetary pinions to rotate in oppositedirections.

Two planetary pinions 41 and 41 engaging the planetary wheels 41 and 41are as usual either loosely mounted upon two stubshafts rigidly securedto the frame or the gear casing 41, which is movable about the axis m-w,or secured upon two stub-shafts loosely revolving in bearings providedfor this purpose in the frame or in the gear casing. An arm 41, which isfastened with the said frame or car casing 41 of the d1tierential, isconecte by the link 43 with the levelcontrolling the rotary check-valveof the plane perpendicular to the axis are directly connected togetherand with one of the axial channels, but not with the other group (Fig.-4). The connection between the two groups is effected through the mediumof two narrow chambers 24 and 29 parallel with the axis anddiametrically o posed to the interior of the check-valve b0 y, thelength of these chambers in the direction of said axis being such thatfor one position of the check-lvalve, the left chamber is connected witha a'adial channel of the front group, while the right one is inconnection with a radial channel of the back or rear group, theconnections for r rection until (Fig. 8) the conduits '33 and bad thehther osition of the check-valve bemg I rious parts of the device arenowready for reversed. he two chambers 24 and 29' are new operation inthe, same direction or for respectively connected through ipes with backoperation in a similar manner. r the front and rear spaces of the rivingpiss With this follow-up dev1ce,the connections ton so that these spacescan be alternatively whlch have been afi'orded upon the two facesconnected with the vacuum and with the at of the piston by the cook 42ulgder the control mosphere, as such is the case with the servo-. of thesaid pedal lever 17 will therefore be motor 10 of Figure 1. sup ressedby the unclutchmg lever as soon The relative position of the conduits 34t y have Producedl thell eflect p n he 32 d 31:, 33 g h b h th t th lpiston; the several parts will consequently r is at least equal to thecommon peripherical wi automatlcaulf to the I P 1 Width f Said d it SupOse h pedal s1t1cn when the drlver releases the pedal 7 lever 7 to berogressivel idlsplaced to h lever, this action being analogous to theone right (clockwise); then t e link 40 causs i m the dlsposltlonprevlously f the crank-lever 41 and the bevel-wheel 41 to b move inanticlockwise direction; the op osite recapltulate, for q ldlsplflqcments 0T wheel4l beingatrest, the wheel 41 will ence controlthe d q mg W revolve so that its center moves to the left the dn'ectlonthe Valve 7111.139 glvell whilst 'at the same time .the center of theangular dlsplacements of substantlauy. the

t 1 same value, but in the opposite directions. g g fi gg gg ggggggg531335315,; Also, within the limits of the stroke which is inanticlockwise direction and the cranli Pliacticauy .auowable for theselevers the-rel lever of the valve4 2rotates in clockwise diatwe posltmnsof the Valve and the outer as t c relative 32' begin to open thechambers 29 and 24 respectively; this first part of the stroke of thearm 16 in the slot 15 corresponds to the lap r of the valve 42, andmerely intercepts the connections of the chambers 24 and v 29 with theatmosphere and the vacuum.

without any action on the piston of the work-. ing cylinder 10 and henceon the unclutching lever 13. But as soon as the pedal lever 17 iscontinued tocbe displaced to the right, the chambers 24 and 29 areprogressively connected with the conduits 32 and 33 respectively (thefull opening correspondingto the second part of the stroke of arm 16 inthe slot 15), now the piston in. the'cylindgr 10 will draw upon thecable 12 and actuate the unclutching lever 13 in the direction to theright.

But this displacement of the lever 13 is transmitted by the link 39 tothe cranklever 41 and the bevel-wheel 41 which are fastened on the sameshaft; saidwheel rotates then in clockwise direct-ion; the bevel-wheel41 being motionless at this time, both the pinions 41 and 41 roll on thewheel 41 sol that the arm 41'. moves in clockwise direction, causingby-means-of the link 43 the cock 30 to rotate in anticlockwise directionuntil the respective edges of the conduits 33 and 29 on the one hand,32"- and 24' on the other hand meet, again together and just interceptthe connections previously made, with the working cylinder 10, thevarious parts of the cock 42 being-a ainin the same relative positionsas" above before the first' opening. -At this instant, the arm 16 of thepedal lever 17 is again in the middle of its stroke in the slot 15; thedevice is at rest and remains in this state as long as the pedal lever17 is kept by -the foot in the considered position. The vapositions ofthe two levers are. not varied. i p I From all the foregoing it isobvious that the desired action of the vacuum prevailing in the inletconduit of the engine which is to. perform the unclutching and tocontrol all the movements in actuating a single cock, will be-obtainedin'a suitable manner by the relative displacements of the'pedal lever 17and the unclutching lever-13 which respectively control-ithe two. valvesof the cock 5; the amount of thesedisplacements will correof the cockwill remain this same as long spond to the stroke of thearm? 16in theslot 15.

" Havingthus dcscribediny apparatus,.what

I claim as new tion, is: v v 1. .Inan engine'group' actuated by an .in-

therein, and my own inventernal combustion engine and comprising a Iclutch. provided with a reaction spring, uns clutchlng means wherein thepower requlred to overcome the resistance of the clutch spring I issupplied "by the vacuum produced b the suction of the engine in theinlet conduit between the engine and the carbu-reter, comprisin an uncluching lever controlling the sald clutch-through the usual means, an un-'I clutching pedal, meansconnectin this latter pedal and lover in suchmanner t at the said lever will be displaced only after the pedal hasbeen moved through a certain'angle, a;

piston movable in a cylinder closedcat the ends, flexible coupling meansconnecting the,

said piston with the unclutching'levena dis-.

tributing cock, two conduits connecting the respective ends of saidcylinder with the said cook, a third conduit connecting said, cock. withthe en ine suction inlet, means'connect-. ing the sait i pedal and leverwith the said cock and adapted in such a manner that-after a ,certainstroke of the pedal (neutral stroke),

ble coupling means without any effect on the unclutching lever andconstant for all positions, every additional displacement (effectivestroke) of said pedal in the same direction will cause the unclutchinglever to effect a displacement. in the same direction and of the sameamplitude.

2. In an engine group actuated by an internal combustion engine andcomprising a clutch provided with a reaction spring, unclutching meanswherein the power required to overcome the resistance of the clutchspring is supplied by the vacuum produced by the V respective ends ofsaid cylinder with the said cook, a third conduit connecting said cockwith the engine suction inlet, a link device connecting the pedal, withthe said cock and adapted to place the side of the piston farthest fromthe said unclutching lever in comconstant for all positions,

tral and inoperative displacement which is causes the unelutehing leverto effect a displacement in the same direction and of the sameamplitude.

In testimony whereof I have hereunto affixed my signature.

HENRI LEON 'MARFAING.

munication with the conduit leading to the engine suction inlet when thepedal is operated, while at the same time connecting the other side ofthe piston with the atmosphere, a second link device connecting the saidunclutching lever withthe said cock and adapted to intercept therespective connec-' tion between the sides of the piston and the enginesuction pipe and the atmosphere when the said lever is displaced throughan angle equal to the angular displacement of the pedal.

3. In an engine group actuated by an internal combustion engine andcomprising a clutch provided with a reaction spring, unclutching meanswherein the power required to overcome the resistance of the clutchspring is supplied bythe vacuum produced by the suction of the engine inthe inlet conduit between the engine and the carbureter, com-.

prising: an unclutching lever controlling the I said clutch through theusual means, an unclutching pedal, an arm disposed thereon, anarc-shaped slot formed in the said lever, wherein the said arm isengaged, a piston movable in a cylinder closed at the ends,flexiconneeting said piston with the unclutching lever, a distributingcock, two conduits connecting the respective ends of said cylinder withthe said cock, a third conduit connecting said cock with the enginesuction inlet, means connecting the said pedal and lever to the saidcock and adapted in such a manner that every displacement of the pedalgreater than a certain neu-

